#include <iostream>
#include <string>
#include <vector>
#include <assert.h>
#include <string.h>
#include <algorithm>
#include <map>
using namespace std;

namespace ouyang
{
	class string
	{
	public:
		typedef char* iterator;
		typedef const char* const_iterator;

		iterator begin()
		{
			return _str;
		}

		iterator end()
		{
			return _str + _size;
		}

		const_iterator begin() const
		{
			return _str;
		}

		const_iterator end() const
		{
			return _str + _size;
		}

		string(const char* str = "")
			:_size(strlen(str))
			, _capacity(_size)
		{
		//	cout << "string(char* str)-构造" << endl;
			_str = new char[_capacity + 1];
			strcpy(_str, str);
		}

		// 拷贝构造
		string(const string& s)
			:_str(nullptr)
		{
			cout << "string(const string& s) -- 拷贝构造" << endl;
			reserve(s._capacity);
			for (auto ch : s)
			{
				push_back(ch);
			}
		}

		void swap(string& ss)
		{
			::swap(_str, ss._str);
			::swap(_size, ss._size);
			::swap(_capacity, ss._capacity);
		}

		// 移动构造
		string(string&& s)
		{
			cout << "string(string&& s) -- 移动构造" << endl;
			// 转移掠夺你的资源
			swap(s);
		}

		string& operator=(const string& s)
		{
			cout << "string& operator=(const string& s) -- 拷贝赋值" <<
				endl;
			if (this != &s)
			{
				_str[0] = '\0';
				_size = 0;
				reserve(s._capacity);
				for (auto ch : s)
				{
					push_back(ch);
				}
			}
			return *this;
		}

		// 移动赋值
		string& operator=(string&& s)
		{
			cout << "string& operator=(string&& s) -- 移动赋值" << endl;
			swap(s);
			return *this;
		}

		~string()
		{
			//cout << "~string() -- 析构" << endl;
			delete[] _str;
			_str = nullptr;
		}

		char& operator[](size_t pos)
		{
			assert(pos < _size);
			return _str[pos];
		}

		void reserve(size_t n)
		{
			if (n > _capacity)
			{
				char* tmp = new char[n + 1];
				if (_str)
				{
					strcpy(tmp, _str);
					delete[] _str;
				}
				_str = tmp;
				_capacity = n;
			}
		}

		void push_back(char ch)
		{
			if (_size >= _capacity)
			{
				size_t newcapacity = _capacity == 0 ? 4 : _capacity *
					2;
				reserve(newcapacity);
			}
			_str[_size] = ch;
			++_size;
			_str[_size] = '\0';
		}

		string& operator+=(char ch)
		{
			push_back(ch);
			return *this;
		}

		const char* c_str() const
		{
			return _str;
		}

		size_t size() const
		{
			return _size;
		}
	private:
		char* _str = nullptr;
		size_t _size = 0;
		size_t _capacity = 0;
	};

/* 这块代码是一个字符串的相加 */
class Solution {
public:
    // 传值返回需要拷贝，右值引用返回
    string addStrings(string num1, string num2) {
        string str;
        int end1 = num1.size() - 1, end2 = num2.size() - 1;
        // 进位
        int next = 0;
        while (end1 >= 0 || end2 >= 0)
        {
            int val1 = end1 >= 0 ? num1[end1--] - '0' : 0;
            int val2 = end2 >= 0 ? num2[end2--] - '0' : 0;
            int ret = val1 + val2 + next;
            next = ret / 10;
            ret = ret % 10;
            str += ('0' + ret);
        }
        if (next == 1)
            str += '1';
        reverse(str.begin(), str.end());
        return str;
    }
};

}

//int main()
//{
//    ouyang::string ret = ouyang::Solution().addStrings("11111111","222222222");
//    cout << ret.c_str() << endl;
//    return 0;
//}
//
int main()
{
    ouyang::string ret;
    ret = ouyang::Solution().addStrings("11111111","222222222");
    cout << ret.c_str() << endl;
    return 0;
}

